Bombus centralis? - male - (Apidae) in the Colorado Mountains at 9000 ft., Park County, Colorado, USA. July 7, 2005. Size: L = 8 mm. Ranges from Rocky Mountains west to Pacific Coast from the foothills to montane elevations (6500-9000 ft). P.A.Byron (1980) found B. centralis at elevations of 6500-9000 ft. Looks very similar to B. flavifrons which lives higher up to subalpine elevations in the Front Range of the Colorado Rockies. IMHO, the two bees are subspecies and should be renamed Bombus flavifrons centralis and Bombus flavifrons flavifrons, respectively. The workers of the two subspecies vary in body length: L = 9-10 mm for B.f.centralis (Colorado Springs) and L = 11-12 mm for B.f.flavifrons (Victor; Twin-Lakes; Breckenridge).